634999 has 6 divisors (see below), whose sum is σ = 670560. Its totient is φ = 601236.

The previous prime is 634979. The next prime is 635003. The reversal of 634999 is 999436.

It is not a de Polignac number, because 634999 - 2⁷ = 634871 is a prime.

It is a Duffinian number.

634999 is a modest number, since divided by 999 gives 634 as remainder.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (634939) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 519 + ... + 1240.

It is an arithmetic number, because the mean of its divisors is an integer number (111760).

2⁶³⁴⁹⁹⁹ is an apocalyptic number.

634999 is a deficient number, since it is larger than the sum of its proper divisors (35561).

634999 is a wasteful number, since it uses less digits than its factorization.

634999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1797 (or 1778 counting only the distinct ones).

The product of its digits is 52488, while the sum is 40.

The square root of 634999 is about 796.8682450694. The cubic root of 634999 is about 85.9523352240.

The spelling of 634999 in words is "six hundred thirty-four thousand, nine hundred ninety-nine".